caif: Use link layer MTU instead of fixed MTU

Previously CAIF supported maximum transfer size of ~4050.
The transfer size is now calculated dynamically based on the
link layers mtu size.

Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: David S. Miller <davem@davemloft.net>

15 files changed, 173 insertions, 69 deletions

diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
index 3e706f00a0d3..3df0c0f8b8bf 100644
--- a/drivers/net/caif/caif_serial.c
+++ b/drivers/net/caif/caif_serial.c
@@ -403,7 +403,6 @@ static void caifdev_setup(struct net_device *dev)
         dev->type = ARPHRD_CAIF;
         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
         dev->mtu = CAIF_MAX_MTU;
-        dev->hard_header_len = CAIF_NEEDED_HEADROOM;
         dev->tx_queue_len = 0;
         dev->destructor = free_netdev;
         skb_queue_head_init(&serdev->head);
diff --git a/include/net/caif/caif_dev.h b/include/net/caif/caif_dev.h
index 318ab9478a44..6da573c75d54 100644
--- a/include/net/caif/caif_dev.h
+++ b/include/net/caif/caif_dev.h
@@ -50,6 +50,9 @@ struct caif_connect_request {
  * @client_layer:       User implementation of client layer. This layer
  *                      MUST have receive and control callback functions
  *                      implemented.
+ * @ifindex:            Link layer interface index used for this connection.
+ * @headroom:           Head room needed by CAIF protocol.
+ * @tailroom:           Tail room needed by CAIF protocol.
  *
  * This function connects a CAIF channel. The Client must implement
  * the struct cflayer. This layer represents the Client layer and holds
@@ -59,8 +62,9 @@ struct caif_connect_request {
  * E.g. CAIF Socket will call this function for each socket it connects
  * and have one client_layer instance for each socket.
  */
-int caif_connect_client(struct caif_connect_request *config,
-                           struct cflayer *client_layer);
+int caif_connect_client(struct caif_connect_request *conn_req,
+                        struct cflayer *client_layer, int *ifindex,
+                        int *headroom, int *tailroom);
 
 /**
  * caif_disconnect_client - Disconnects a client from the CAIF stack.
diff --git a/include/net/caif/caif_layer.h b/include/net/caif/caif_layer.h
index 25c472f0e5b8..c8b07a904e78 100644
--- a/include/net/caif/caif_layer.h
+++ b/include/net/caif/caif_layer.h
@@ -15,14 +15,8 @@ struct cfpktq;
 struct caif_payload_info;
 struct caif_packet_funcs;
 
-#define CAIF_MAX_FRAMESIZE 4096
-#define CAIF_MAX_PAYLOAD_SIZE (4096 - 64)
-#define CAIF_NEEDED_HEADROOM (10)
-#define CAIF_NEEDED_TAILROOM (2)
 
 #define CAIF_LAYER_NAME_SZ 16
-#define CAIF_SUCCESS    1
-#define CAIF_FAILURE    0
 
 /**
  * caif_assert() - Assert function for CAIF.
diff --git a/include/net/caif/cfcnfg.h b/include/net/caif/cfcnfg.h
index 9fc2fc20b884..bd646faffa47 100644
--- a/include/net/caif/cfcnfg.h
+++ b/include/net/caif/cfcnfg.h
@@ -7,6 +7,7 @@
 #ifndef CFCNFG_H_
 #define CFCNFG_H_
 #include <linux/spinlock.h>
+#include <linux/netdevice.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfctrl.h>
 
@@ -73,8 +74,8 @@ void cfcnfg_remove(struct cfcnfg *cfg);
 
 void
 cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
-                     void *dev, struct cflayer *phy_layer, u16 *phyid,
-                     enum cfcnfg_phy_preference pref,
+                     struct net_device *dev, struct cflayer *phy_layer,
+                     u16 *phyid, enum cfcnfg_phy_preference pref,
                      bool fcs, bool stx);
 
 /**
@@ -114,11 +115,18 @@ void cfcnfg_release_adap_layer(struct cflayer *adap_layer);
  * @param:              Link setup parameters.
  * @adap_layer:         Specify the adaptation layer; the receive and
  *                      flow-control functions MUST be set in the structure.
- *
+ * @ifindex:            Link layer interface index used for this connection.
+ * @proto_head:         Protocol head-space needed by CAIF protocol,
+ *                      excluding link layer.
+ * @proto_tail:         Protocol tail-space needed by CAIF protocol,
+ *                      excluding link layer.
  */
 int cfcnfg_add_adaptation_layer(struct cfcnfg *cnfg,
                             struct cfctrl_link_param *param,
-                            struct cflayer *adap_layer);
+                            struct cflayer *adap_layer,
+                            int *ifindex,
+                            int *proto_head,
+                            int *proto_tail);
 
 /**
  * cfcnfg_get_phyid() - Get physical ID, given type.
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index e2b86f1f5a47..0b586e9d1378 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -255,7 +255,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
                         pref = CFPHYPREF_HIGH_BW;
                         break;
                 }
-
+                dev_hold(dev);
                 cfcnfg_add_phy_layer(get_caif_conf(),
                                      phy_type,
                                      dev,
@@ -285,6 +285,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
                 caifd->layer.up->ctrlcmd(caifd->layer.up,
                                          _CAIF_CTRLCMD_PHYIF_DOWN_IND,
                                          caifd->layer.id);
+                might_sleep();
                 res = wait_event_interruptible_timeout(caifd->event,
                                         atomic_read(&caifd->in_use) == 0,
                                         TIMEOUT);
@@ -300,6 +301,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
                                    "Unregistering an active CAIF device: %s\n",
                                    __func__, dev->name);
                 cfcnfg_del_phy_layer(get_caif_conf(), &caifd->layer);
+                dev_put(dev);
                 atomic_set(&caifd->state, what);
                 break;
 
@@ -326,7 +328,8 @@ struct cfcnfg *get_caif_conf(void)
 EXPORT_SYMBOL(get_caif_conf);
 
 int caif_connect_client(struct caif_connect_request *conn_req,
-                           struct cflayer *client_layer)
+                        struct cflayer *client_layer, int *ifindex,
+                        int *headroom, int *tailroom)
 {
         struct cfctrl_link_param param;
         int ret;
@@ -334,8 +337,9 @@ int caif_connect_client(struct caif_connect_request *conn_req,
         if (ret)
                 return ret;
         /* Hook up the adaptation layer. */
-        return cfcnfg_add_adaptation_layer(get_caif_conf(),
-                                                &param, client_layer);
+        return cfcnfg_add_adaptation_layer(get_caif_conf(), &param,
+                                        client_layer, ifindex,
+                                        headroom, tailroom);
 }